1. Technical Field of the Invention
The present invention relates to a curved display, particularly to a curved display apparatus and a gamma correction method thereof.
2. Description of the Related Art
With the popularity of the liquid crystal display device, various products manufactured by different technology are proposed, and the curved display apparatus is becoming noticed by the public in the market. In theory, when the curved display apparatus is given a consistent control signal in the whole surface, the same hue should be observed in each region of the curved surface, but in reality, the observed hue is not actually the same. Taking the convex surface display device for example, due to the characteristics of the liquid crystal display, if the observation is along a certain normal, most of the light emitted from the regions close to the observation point on the curved surface or the regions of almost 0° angle of view is directly received by the observer, and theoretically the display brightness of the said regions is brighter than the those with farther distance or larger angle of view (the definition of the angle of view corresponding to a certain point on the curved surface is the angle between the normal of that point and the said observation direction). Still, in practice, when the control signal instructs certain colors, partial color shift appears in the curved display apparatus, so that the regions with almost 0° angle of view are darker than those with larger angle of view instead. As shown in FIG. 8, when the grayscale values of white balance decreasing from 255 to 0 instructed by the control signal are given, the decreasing rate of the display brightness is higher if the angle of view is closer to 0° from 40°, and the brightness of each region of the curved surface with the grayscale value under 180 is in reverse.